Grain oriented electromagnetic steel sheets having a very low iron loss
AssigneeKawasaki Steel Corporation
InventorsUjiihiro Nishiike, Yasuhiro Kobayashi, Hirotake Ishitobi, Shiqeko Sujita, Norio Takahashi, Hisanao Nakahara, Yukio Inokuti
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Abstract
A grain oriented electromagnetic steel sheet having a very low iron loss is obtained by subjecting a surface of base metal in the sheet after finish annealing to a particular mechanical polishing and has a surface roughness having a center-line average roughness of not more than 0.3 .mu.m after the polishing and the number of abrasive grains embedded in a layer just beneath polished surface of not more than 20,000 grains/cm.sup.2.
Claims5
A grain oriented electromagnetic steel sheet having a very low iron loss, wherein a surface of base metal in said steel sheet after finish annealing has a surface roughness having a center-line average roughness of not more than 0.3 .mu.m through a mechanical polishing of giving a slight strain to said base metal surface, whereby abrasive grains are embedded in a layer just beneath the polished surface and the number of abrasive grains embedded is not more than 20,000 grains/cm.sup.2.
Dependencies are inferred from the claim text.